MS hides it under 10 feet. But if we use a rule of thumbs with PS4 having about 45% PS+ subs, then with X1 I think about 50% would be a good measure (so 15-20M subs to gold).
PSNow is under 2M, so Gamepass probably also on the 1-2M subs.
SW sales still makes most of the revenue, and for that if they don't have the platform they miss most since most of the SW sold on Xbox is 3rd party.
Gamepass is probably closer to 4m.